This invention relates generally to the field of soft-covered buildings and more specifically relates to the design of a strengthened panel arch therefore.
Soft-covered buildings are well known in the art, consisting of a number of supports anchored to a base and spaced apart by purlins or other braces. These supports often take the form of arcuate apparatus which, in conjunction with the purlins joining them, allow for the attachment of a soft fabric cover thereover, yielding a soft-covered building. These soft-covered buildings are economical to produce and can be rapidly erected.
Demand exists for increased size in these types of buildings.
The main limiting factor in building size is to be able to provide arch-shaped supports that are strong enough to withstand the loads associated with such a larger building. For example the cover of a larger building is heavier requiring greater strength in the supports, and the weather elements such as wind, or even in some cases earthquakes, can have greater effect on a larger building and this needs to be accommodated in building design.
It is an object of the present invention to provide a reinforced panel arch for soft-covered buildings and the like, which will allow for the construction of said arch from standard arcuate panel sections with the addition of stiffening elements to increase the strength of such an arch.
It is specifically contemplated that the arcuate panel sections to be used to build said arch would be corrugated steel panels, such as those used in the construction of steel quonsets or grain bins. These sinusoidally corrugated panels have considerate inherent strength of their own and an arch built of such panels should be useful in the construction of a soft-covered building provided that the arch can be significantly reinforced to add to the strength provided by the corrugations in the panel sections.
The basic panel arch produced by the attachment of one or more arcuate corrugated panel sections would be strengthened by the addition of stiffening elements thereto, in order to direct forces or loads exerted on or near the top of said arch down to the base of the arch and its base attachment and to distribute these loads without bending or otherwise damaging the arch.
Thus the invention, a reinforced panel arch for a soft-covered building or the like, accomplishes its objects comprising an arch comprised of at least one panel section, said arch having an underside and two base ends and a center point equidistant along the arch from each base end; and stiffening means attached along the underside of said arch.
The panel sections which are specifically contemplated are corrugated steel panels, similar in construction to those used in the construction of steel quonset buildings known previously in the art. The main difference between the panels contemplated for use here and those used in the construction of a conventional steel quonset would be width. While a sinusoidally corrugated panel used to construct a steel quonset might be four or more corrugations wide (typically on 24 inch centers), it is contemplated to use a panel of two corrugations in width in this case to lessen the weight and cost of the arch. It will of course be understood that panels of varying widths and constructions, with or without corrugations, could be used without departing from the scope of the claimed invention so long as these panel sections when joined together form an arch, having an underside to which the stiffening means can be attached.
As mentioned above, the stiffening means would be attached to the underside of the assembled panel arch in order to allow for a smooth and unobstructed upper surface on the arch. It is important to have a smooth upper surface on the arch so that for example in the case of a fabric covering being placed thereon to yield a soft-covered building there are as few protrusions as possible which might cause the fabric covering to rub or tear in the wind or other conditions.
In the case of corrugated panel sections being used to assemble the arch, the stiffening means could be attached in the channel between two downward-facing corrugations, so as to obscure as little of the open space defined within the arch while maintaining the position thereof on the underside.
Anchoring hardware could be placed at each base end of the assembled arch to allow the arch to be anchored to the surface to which the arch and/or building is to be attached. Various types of anchoring hardware could be used and insofar as they accomplish the objective of allowing the arch to be attached to a surface or other item it will be understood that all such variations and types of hardware are contemplated within the scope of the present invention.
Various types of stiffening means could be used to add strength to the arch in addition to any strengthening effect exhibited by any corrugations in the panel sections. The first type of stiffening means which is specifically contemplated is the attachment of hard braces along the underside of the arch. One or more braces could be attached between two points on the underside of the arch to add strength to the arch in its standing position and increase its ability to deal with the loads exerted on a soft-covered building.
It is specifically contemplated that one type of bracing arrangement which could be used would be to employ two straight first braces equal in size. Each straight first brace would be attached at or near the center point of the arch extending towards one of the base ends of the arch. The other end of each first brace would then be attached to the underside of the arch at an attachment point nearer to the respective base end of the arch. This would assist in the transfer of forces exerted near the top of the arch down along the arch closer to the ground.
The utility and efficiency of the first braces might be improved by the addition of a pair of second braces, straight also and equal in size. Each second brace would be attached to the underside of the arch near the point of attachment of one of the first braces to the arch furthest from the center point. The other free end of each second brace would then be attached to the underside of the brace, again closer to its respective base end.
Further pairs of braces might be added in a similar fashion.
The braces might be straight, or might in some fashion be shaped to accommodate the shape of the arch while assisting in the transfer of force exerted on the arch to the base.
A second method of stiffening the arch which is contemplated would be to use a tensioning apparatus. A series of eyelets could be attached along the underside of the arch in the direction of each base end and a cable fed therethrough. A tensioner, such as a turnbuckle or the like, could then be used to tighten this cable. One eyelet could be placed at the center point of the arch, and other eyelets could be placed in corresponding pairs towards the base ends of the arch.
A reinforced panel arch is disclosed comprising an arch comprised of one or more panel sections, said arch an underside and having two base ends and a center point equidistant along the arch from each base end; two equally sized straight first braces, each first brace attached to the underside of the arch at its one end at or near the center point of the arch and extending towards an opposing base end of the arch and being attached at its other end at a point towards said opposing base end; and two straight second braces of equal length, each second brace being attached to the underside of the arch at its one end at or near the point of attachment furthest from the center point of a first brace to the arch and being attached at its other end to the arch at a point closer to the closest base end of the arch.
Also disclosed is a reinforced panel arch comprising an arch comprised of one or more panel sections, said arch an underside and having two base ends and a center point equidistant along the arch from each base end; and a tensioning apparatus attached along the underside of the arch, said tensioning apparatus comprising a plurality of eyelets displaced along the underside of the arch, wherein one eyelet is at the center point of the arch, and other eyelets are in pairs equidistant from and on either side of the center point of the arch; a cable running freely through said eyelets from the eyelet closest to one base end of the arch to the eyelet closest to the other base end of the arch; and a tensioner to tighten said cable.
It will be understood that other types of stiffening means could be used to strengthen the arch also and insofar as they involve the attachment of stiffening or strengthening elements along the underside of the arch they will be contemplated within the scope of the present invention.
Also disclosed is a frame for a soft-covered building comprising a plurality of panel arches joined in a spaced-apart relationship by a plurality of purlins, wherein each panel arch is a panel arch of the present invention.